Typically, Woo amps are sold factory direct on a build-to-order basis, so that customers have the option of buying standard-version Woo models or of having their new amps factory “hot-rodded” with various extra-cost tube upgrade options. The WA22 amp ($1900 in standard form, or up to $2450 with every available tube upgrade) is a fully balanced, transformer-coupled headphone amplifier that is--in terms of price--positioned at an upper-middle point within Woo’s impressive nine-model amplifier lineup. As you can well imagine, these guys eat, sleep, and breathe high-end headphone amplifier designs.
Setting the Context
For those of you unfamiliar with the modern high-end headphone marketplace, some of the players like Woo Audio may be unfamiliar so that some context may prove helpful.
Any list of modern headphone makers would include familiar names such as AKG, Audio-Technica, Beyerdynamic, Denon, Grado, Sennheiser, Stax, and Ultrasone, along with a smaller group of relative newcomers such as Audeze and HiFiMan. When we work back up the signal chain to look at high performance headphone amplifier makers, however, a mostly new group of companies emerges. While some brand names will no doubt be familiar to traditional high-end audiophiles (e.g., Grado), there are many key players in the high-end